The overall objectives of this work are to ascertain the presence of immune complexes in the serum of patients with certain allergic diseases in the skin. In addition, we are evaluating the mechanisms of tissue injury in these diseases as well as the role played by the immune complexes in initiating the inflammation. We have established selected assays for the measurement of immune complexes in our laboratories and have modified existing assays to enable us to measure IgA or IgM-containing complexes. The composition and molecular characteristics of complexes is presently being investigated, with particular attention paid to the composition of antigenic-components that are part of the aggregates. The Raji cell radioimmune assay and I125 Clq binding assay are given particular attention, but assays using immunoconglutinin and monoclonal rheumatoid factor are also being developed.